Question

我有我的main.cpp：

#include <boost/thread.hpp>

#include "../headers/BoostUDPSender.h"
#include "../headers/UDPListener.h"
#include "../headers/UDPPacket.h"

using namespace std;

int main(int argc, char** argv) {

        cout << argv[1] << endl;
        cout << argv[2] << endl;

        BoostUDPSender boostUDPSend;
        boostUDPSend.boostUDPPacket(argv[1], argv[2]);
}

和我的BoostUDPSender.h

#ifndef BOOSTUDPSENDER_H_
#define BOOSTUDPSENDER_H_

class BoostUDPSender {
public:
    BoostUDPSender();
    int boostUDPPacket(char* ipStr, char* port);
};

#endif /* BOOSTUDPSENDER_H_ */

和BoostUDPSender.cpp

#include "../headers/BoostUDPSender.h"
#include <string>
#include <iostream>
#include <boost/array.hpp>
#include <boost/asio.hpp>
#include <arpa/inet.h>

using boost::asio::ip::udp;
using namespace boost::asio::ip;

BoostUDPSender::BoostUDPSender() {
}

int boostUDPPacket(char* ipStr, char* port){

      try
      {
        boost::asio::io_service io_service;

        udp::resolver resolver(io_service);
        udp::resolver::query query(udp::v4(), ipStr, port);
        udp::endpoint receiver_endpoint = *resolver.resolve(query);
        udp::socket socket(io_service);
        socket.open(udp::v4());
        boost::array<char, 1> send_buf  = {{ 0 }};
        socket.send_to(boost::asio::buffer(send_buf), receiver_endpoint);

        boost::array<char, 128> recv_buf;
            udp::endpoint sender_endpoint;
            size_t len = socket.receive_from(
                boost::asio::buffer(recv_buf), sender_endpoint);

            std::cout.write(recv_buf.data(), len);
          }
    catch (std::exception& e)
      {
        std::cerr << e.what() << std::endl;
      }

      return 0;
    }

这一切对我来说都很好，但是当我编译时（下面包含的其他文件，与上面的内容无关）：

g++ UDPListener.cpp UDPPacket.cpp BoostUDPSender.cpp main.cpp -o main -lboost_thread -lboost_system -lpthread -std=c++11

我明白了：

/tmp/ccFPtASO.o: In function `main':
    main.cpp:(.text+0x8f): undefined reference to `BoostUDPSender::boostUDPPacket(char*, char*)'
    collect2: error: ld returned 1 exit status

我不明白boostUDPPacket()是如何定义的，我是以传统的方式创建我的对象并在其上调用方法？

Answer 1

您不是将该函数定义为成员函数，而是将其定义为免费（非成员）函数。

从

更改定义

int boostUDPPacket(char* ipStr, char* port){

到

int BoostUDPSender::boostUDPPacket(char* ipStr, char* port){
//  ~~~~~~~~~~~~~~~~

main.cpp :(。text + 0x8f）：未定义引用[object＆＃39; s方法]

1 个答案: